Specifications

MODEL 300 COMBUSTION ANALYZER

5-14 Instruction 24-9223

5.7 OPTIONAL SENSOR BIAS BATTERY REPLACEMENT

Four “AA” batteries mounted behind the control panel apply a constant

bias voltage to the NO

and/or SO

sensor(s). The batteries should last a

minimum of 6 months, with a typical life expectancy of 9 months to more

than 1 year.

Replace the batteries when the LOW BATT message appears on the

auxiliary display panel. You have approximately 1 month of operating

time left after the first LOW BATT message is displayed before the

batteries go completely dead, as indicated by the BATT FAIL message.

Replace the batteries as follows:

Equipment and Materials Needed:

• Medium Flat-Blade Screwdriver • Four “AA” Alkaline Batteries

Procedure:

1. Remove control panel per Section 4.1 in this manual.

2. Tilt the control panel upwards until the four “AA” batteries become

accessible (Fig. 5-7).

3. Replace batteries with four fresh “AA” alkaline cells in the proper

polarity.

If batteries are installed incorrectly, the BATT FAIL message appears

on the auxiliary-display panel after analyzer is powered on and run

through its calibration cycle.

The SO

sensor stabilizes within 15 minutes after the application of

bias voltage.

Depending on how long the NO

sensor was without bias voltage, the

time required for this sensor to stabilize varies from less than a

minute to several days. Typical stabilization times are shown below: